In the electromechanical industry, the so-called medium voltage double power supply change-over switch in the current market is composed of two medium voltage circuit breakers. The volume is huge. Moreover, the so-called medium voltage double power supply change-over switch only has the electrical interlocking function. In addition, the interlocking reliability is low, which cannot meet the demand of the modern market. Thus, developing a medium voltage double power supply change-over switch with an integrated structure, small size, and reliable mechanical and electrical interlocking has become an inevitable trend.